A magnetic resonance imaging apparatus is an imaging apparatus which excites nuclear spin of a patient placed in a static magnetic field with an RF (Radio Frequency) pulse having the Larmor frequency and generates a reconstructed image by using the magnetic resonance signals emitted from the patient due to the excitation.
In many cardiac examinations using a magnetic resonance apparatus, first, six reference planes useful for diagnosis are selected, and then imaging of various still images and moving images in accordance with diagnostic purposes is performed at the respective selected reference planes.
Here, the six reference planes means a vertical long axis plane, a horizontal long axis plane, a short axis plane, a two-chamber long axis plane, a three-chamber long axis plane and four-chamber long axis plane.
Conventionally, in order to set the six reference planes, the method of repeating processes of positioning and imaging in the following manner has been used. In this conventional method, the position of the vertical long axis plane is determined from an axial cross-sectional image, then the position of the horizontal long axis plane is determined from the vertical long axis view imaged at the determined position of the vertical long axis plane, then the position of the short axis plane is determined from the horizontal long axis view imaged at the determined position of the horizontal long axis plane, and positioning and imaging are repeated in this manner (this method is sometimes referred to as a chain oblique technique, because it is a method of repeating positioning and imaging of oblique cross-sections).
Conventional technology based on the chain oblique technique requires wide experience and highly advanced skills in order to secure accuracy of setting cross-sectional positions, in addition to its complicated procedure. This is because the positional error of the previously determined cross-section influences the position of the subsequently determined cross-section. In addition, because considerable time is required for setting the six reference planes, it imposes a significant burden on a patient.
Then, technology of detecting anatomical features of the heart and automating setting of the six reference planes has been developed.
However, the conventional technology merely relates to a technology for automatically setting the above six reference planes and does not relate to a technology for setting cross-sections useful for cardiac diagnosis other than the six reference planes. For example, although kinetic observation of valves such as an aortic valve and a pulmonary valve is required in examination of valvular disease, sufficient automation has not been achieved as to setting of cross-sections appropriate for the kinetic observation of these valves. In addition, although dynamic information on blood flow velocity and passage diameters adjacent to valves such as an aortic valve and a pulmonary valve is necessary for understanding cardiac hemodynamics, sufficient automation has not been achieved as to setting of imaging cross-sections appropriate for measuring blood flow velocity and passage diameters.
Then, a magnetic resonance apparatus, that can automatically set cross-sections useful for cardiac diagnosis such as a cross-section appropriate for the kinetic observation of valves and a cross-section appropriate for understanding cardiac hemodynamics other than the six reference planes, has been desired.